Throughout the years, there has been a desire to alter the color of synthetic and natural fibers. In particular, coloring of human hair has been sought in view of changing styles and fashion. However, due to the inherent composition of hair fiber, and the chemical and mechanical exposure encountered by the hair fibers during normal care and styling, obtaining and maintaining a precise color has been an illusive goal that requires constant improvements in technology.
As is well known, hair is composed of a unique protein material called “keratin” which is repeatedly being subjected to both chemical and mechanical damage from combing and brushing, as well as from sunlight, chlorinated water, shampooing, permanent waving, and other such treatments involving various chemicals. As a result, depending upon the length of the hair fiber, the distal ends of each hair fiber tend to have substantially more damage than the proximal ends nearer to the scalp. This inconsistency may cause variation in the dye uptake by the hair fiber, resulting in color variations along the length of the hair fiber.
In spite of the long history with the coloration of hair and the extensive effort that has been expended in attempting to eliminate the problems associated with the dyeing of human hair, no system has been achieved which is capable of overcoming all of the drawbacks and difficulties encountered with hair dyes. Included among these drawbacks is the need for a two component system in permanent hair coloring technology.
Temporary dyes or hair colors last through a few shampooings, while semi-permanent hair colors are retained for three to six weeks of shampooings. The permanent dyes or colors, which are often equally employable on plant derived and synthetic fibers, as well as hair keratin, cannot be shampooed out from hair fibers.
In virtually all prior art, using permanent hair dyes requires hydrogen peroxide along with the particular dyestuffs. During the application, the mixture enters into the hair fibers and reacts therein to form larger dyes of a predetermined color. Since the dye molecules formed are larger than the molecules entering the hair fibers, the formed dyes are trapped within the hair fibers, and are unable to diffuse out of the fibers. Consequently, the resulting coloring is trapped within the hair fiber and is permanent.
One advantage that has been found from using these types of dye mixtures is the ability to lighten hair, since the presence of both hydrogen peroxide and the alkaline environment of the mixture will also remove natural hair color, which is then replaced by the colors formed in situ.
One problem which is typically encountered in virtually all prior art permanent hair coloring compositions is a requirement that the hair color and peroxide must be distributed as two components, in two separate and independent containers. Both components require suitable and often costly containers and have to be additionally housed in the outer box. One container is employed for storing the hair dye precursors and alkali, while the second container is employed for storing hydrogen peroxide, which is unstable at high pH. When actual use of the hair coloring composition is desired, the contents of the two containers are intermixed and immediately applied to the hair fibers. The unused color needs to be wasted since all of the dye stuff has reacted.
In addition to being less expensive, a single container can have a number of advantages. Traditional oxidative hair color is sold in single applications. A single container hair color can be used for multiple applications and can dramatically minimize the amount of wasted color. Another commercial problem is inability to sample consumers with hair color prior to purchase, since the two-container package is expensive. Single containers can be offered in a small packet as a sample.
Although some prior art hair dyeing compositions purport to provide a single component system, these prior art systems employ urea, sodium phosphate, citric acid, and/or sodium carbonate perhydrates or percarbonates as lightening and oxidizing ingredients. These materials, commonly used in bleaching, give more damage to hair than traditional hydrogen peroxide lighten-ers. There are no products presently available in this field which employ hydrogen peroxide liberating compounds which are safe to handle and readily mix with water to give the desired hair color and composition achieved by the present invention.
Therefore, it is a principal object of the present invention to provide a permanent or long-lasting dye composition for use on human hair which effectively achieves a single component system comprising stable dry powder, which is storable in a single container and is easily used and safely handled by an operator for achieving a desired hair coloring effect.
Another object of the present invention is to provide a permanent or long lasting dye composition for use on human hair which is capable of being easily and successfully employed on all desired hair fibers with consistent, repeatable and predictable coloration results.
A further object of the present invention is to provide a permanent dye composition having the characteristic features described above which is long lasting and durable color, incapable of being washed from the fibers.
Other and more specific objects will in part be obvious and will in part appear hereinafter.